On Thu, Apr 6, 2017 at 8:32 AM, Jed Brown <[email protected]> wrote: > Matthew Knepley <[email protected]> writes: > > Okay, that makes sense. If I do not have fluxes matching the sources, I > do > > not > > preserve montonicity for an advected field. I might need this to machine > > precision > > because some other equations cannot tolerate a negative number there. I > will > > write this one down. > > > > Why do I need it "for a projection in a staggered grid incompressible > flow > > problem". > > This would mean I satisfy (I think) > > > > \int_T div p = 0 > > Matt Knepley can take the divergence of a scalar.
Yes, I forgot the grad. It is crazy here. Same question. Matt > > meaning that there is a force balance on each cell to machine precision. > If > > I just care > > about the fluid flow, this does not seem important. > > -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener
